Electric heater



E. DELILLE.

ELECTRIC HEATER.

APPLICATION FILED MAY12, 1919.

1,373,1 1 7. t Patented Mar. 29, 1921.

Fig, 1

UNITED STATES PATENT OFFICE.

EDMoND DEILILLE, or Lyon, EEANCE ELECTRIC HEATER.

" Application led May 12, 1919. Serial No. 296,630.

perature by the electric current passing through it. This resistance has generally been placed on or in asbestos, refractory earth or other incombustible matter. The heat developed` is utilized, either directly. as in radiators, or indiretly by the use of parts made of metal whichis a good conductor of the heat, said parts heated by conductibility. In. the latter case the re-v sistance or its incombustible support is in direct contact with the heating members the resistance is therefore impr1soned inap space void of air. The result is that the resistance has rst to transmit calories to an athermanous body, the volume of which takes a comparatively long time to attain the degree of desired normal temperature.

The device which forms the object of the invention is essentially characterized by the fact that the resistance is insulated from any Contact with a heating member and that it is lsuspended inside a closed inclosure without communication with the atmosphere. This inclosure assumes various forms which vary with the apparatus and their applications, but it is always wholly or in part composed of metals which are conductors of heat. The` temperature to which the resistance is brought at the p-assage of the electric current is utilized, in

" this device, on the one hand to heat the air contained in the closed inclosure, on theV other hand to heat by its radiations the inner surfaces of the in closure which are thenmost directly exposed to said radiations.

The annexed drawing illustratesvby way of eXamplethe application of the invention to the heating of a smoothing-iron. Figure l is a longitudinal section: Fig. 2 is a plan view as seen from below -of the resistance and its support removed from the iron.

Theiiron is composed of two fhalf-shells a and fu, The lower half fu is hollowed out as at L Z, Fig. 1 and provided with bosses h1 Z1 for the purpose hereinafter described.

The lange c surrounding the lower halfshell'o is provided withan interior groove j, into which is fitted a plate Z seen in detail in Fig. 2. This plate is formed of asbestos, cardboard, or of'any other insulating materials sufficiently rigid and capable of forming a joint. The upper shell a', is insulated from the flange of the lower shell a: by the plate (Z and it rests on the latter by means of a rib 7' of smallsurface.

By this construction, cavities h Z are left in the iron beneath the plate d and cavities 7c above the plate.

The resistance g is wound'spirally around" a metal armature b, preferably of pure nickel or a suitable alloy, the armature being insulated by a suitably luted braiding of asbestos, in order to prevent it disaggregatmg. The spirals of the resistance are of such dia-meter that the air can circulate a good output owing to convexion. This heating element is secured underneath the plate cZ'by means of threads f of asbestos passing through the plate. At the point of the armature is arranged a cross-piece of refractory material mito which is se cured the xing thread f. These asbestos threads f are vthen coveredrwith a cement in order toavoid disaggregation and also in order to insure the securing of the heating element to the plate. VThe ends of the resistance g are nipped in the bent partof contact plates of copper p and a4 respectively, which pass through the plateand are irmly held thereto by suitably folding them as shown in Fig. l.

The body lznof the iron, the plate d, and the cover shell a are, for example, connected by means of screws t or of pins, separated from the handle -support y, by insulating disks. The cover shell a is formed with a raised portion a1 on which are fixed two contact pins z', thebase of which projects inside the cover. The. said pins are arranged opposite the plates p and a in ordel.`

the electric current runs over the resistance g and makes it red-hot; the air inclosed be'- tween the two shells immediately is heated v and quickly attains a. very high temperature: on the other hand, the direct radiations emitted by said resistance heat the bosses and the inner wall of the shell fv. The latter is consequently heated under the working of both these emissions and attains a relatively high temperature which is kept const-ant so long as the current runs through the resistance.

As soon as the electriccircuit is broken this temperature is lowered, since the source of heat is cut off, but the body o only cools very slowly, owing to the air-tightness of the two shells, which does not allow the outer air to penetrate into the inner chamber and enables the inclosed air to remain hot for a relatively long time.

By varying the thickness of the heating walls, the length and diameter of the resistance wire, the temperature which the apparatus is to attain will be easily determlned.

Accordmg t0 the various appllcatlons of thls invent1on,the lnclosure will recelve various shapes suitable for the use of the respective apparatus. The resistance will also be of the desired shape and of dimensions calculated in proportion to those of the closed chamber-inwhich it will be placed.

What I claim as m to secure by Letters States is l 1. In an electric heater, the combination of a member to be heated having a chamber therein; an electricheating element located in said chamber, the latter being of such size relative to the heating element as to inclose a predetermined' volume of. air vsurrounding the heating element on all sides; an incombustible support for said reatent of the United sistance; and means for supporting saidl support in said chamber, said chamber being constituted by two Ihollow members, hermetically sealed at'their junction and said last named means beinglocated at said junction.

2. An electric sadiron comprising a base portion; an upper portion superposed-gon the base portion,` said base and upper portions being hollow and constituting an air chamber When assembled in superposed relation; a platelike, resistance carrying element ininvention and desire terposed between the base portion and the upper portion; and means carried by the base and upper portions for holding said plate in said air chamber between the upper and lower portions.

' 3. An electric sad iron comprising a base portion; an upper portion superposed on the base portion, said base and upper portions being hollow and constituting an air chamber when assembled in superposed re'- lation; a plate-like, incombustible resistance carrying element interposed between the .ba-se portion and the upper portion; and

means carried by the base and upper portions for holding said plate in said air cham-v ber between the upper and lower portions.

4. An electric sad iron comprising a base portion; an upper portion superposed on the base portion, said base and upper portions being hollow and constituting an air chamber when assembled in superposed relation; a plate-like, resistance carrying element interposed between the .base portion and the upper portion; and a ledge carried circumferentially on said base portion for carrying said plate. V

5. An electric iron comprising three distinct and separate units, to wit, a base, a

cover, and a plate-like, resistance carrier,.

the latter being interposed between the base and the cover; screws passmg through the cover and threaded into the base7 said units being structurally separate' before said screws are set and tightened; plug-contact terminals carried by the cover; and' means, carried by the plate-like resistance carrying unit and connected to the resistance, adapted to make contacting engagement with parts of said plugcontact terminals of the cover unitwhen said units are assembled and secured in place by said screws.

v 6. In an lelectric iron, the combination of a member to be heated comprisingan upper member and a base member spaced to provide an air chamber between them; a Aplate element interposed between said portions; and a resistance element suspended from said'plate; said resistance element sloping downwardly from they heel ofthe iron toward the toe thereof to cause the heating effect ofthe resistance on the base portion to be greater at the forward part of the iron.

In witness whereotl I have. signed .this specification in the presence of two witnesses.

EDMON D DELILLE. Witnesses:

GASTON JEANNIAUX, CLARINGAN. 

